Carburetor



oct. 1s, l1932.

M. MENNEssoN CARBURETOR Filed Sept. 8, 1951 4 Sheets-Sheet l Marce!Mezzzzas'on Oct. 18, i932,

M, MENNESSON 1,883,809

CARBURETOR 4 Sheets-Sheet 2 Filed spt. v8, 1931 T" @Mm @at l; 1932. M.MENNEssoN GARBURETOR Filedvsept. 8', 1931 4 Sheets-Sheet 3 f l N l Ilffamy.- @www Det. 18, 1932. M. MENNEssoN 1,883,809

GARBURETOR Filed sepas, 1931 4 sheets-Sheet 4 Patented Oct; 18, 1932UNITED' STATES PATENT OFFICE MARCEL MNNESSON, 0F NEUILLY-ON-THE-SEEINE,FRANCE, ASSIGNOR TO SOCIETE CARBUBETOB Application led September 8,1931, Serial No. 561,749, and in Belgium Iune, 1981.

The v resent invention relates to carburetors, an more particularly, tothose of the type wherein a small auxiliary carburetor cooperates vviththe main carburetor assembly during starting and operation with a coldmotor.

@ne of the objects ofthe invention is to provide a carburetor assemblyin which means aro provided for preparing the main nozzle for operationas soon as the auxiliary carburetor is cut out.,

nAnother object isito so position the feed orice communicating with theauxiliary car buretor that the explosive mixture enter= ing the intakemanifold is properly distributn ed to the various cylinder vlilurtherobjects will appear inthe course of the detailed description now to begiven with reference to the accompanying draw ings, in whichz` l Figureis a section taken on line 1-1 of Figure 2 to be described and showingone illustrative embodiment of the invention;

Figure 2 is a side view of the structure represented in Figure 1; 1

F'gures 3 and t are sections showing cer= 'tain details of the assemblyillustrated in a system of conduits such as those shown` in Figure 1; amain nozzle 3 also supplied with fuel from the constant level chamber,this nozzle being of any desired type, but preferably of one such as isrepresented in igure 1; an auxiliary mixing chamber l positioned abovenozzle 2; a main mixing chamber 5 receiving fuel from nozzles 2 and 3; abutterdy or similar type of throttle valve 6 mounted so that, in closedposition, it completely closes mixing chamber t and covers y duit 13provided with an emulsifying air inlet 14, amixing chamber 15, a passage16 communioatingat one extremity with main mixing chamber 5 at a pointdownstream ward with relation to throttle valve t, the point ofcommunication with mining chamber 5 being positioned to lie aloneV1 theanis of symmetry of an intake manifold 36 having branches 3'? and 38each feeding a like number of cylinders, passage 16 being formed so asto be able to communicate with chamber 15 under conditions to bedescrild, a shaft 17 of square or polygonal section rotatably supportedin a pair of journals 19 and 20, a lever 13 rigidlyattached to shaft 17and connected to theA dash board by any convenient form of transmission(not shown), a cover element 21 provided with a pair of air intakeorices 32 and 33, a plate 22 having a central opening therein ofsquareor polygonal form adapted to t over the correspondingly sha ed portionof shaft 17, late 22 having a rst elongated opening v 2 (Figures 3 and4) formed therein and adapted to control communication between chamber15 and passage 16 when shaft 17 is rotated, plate 22 being furtherprovided with a circular orifice 28 a passage 29 having one extremitypositioned to communicate with mixing chamber 5 at a point upstreamwardwith relation to throttle valve 6 and having its other extremitypositioned to communicate with chamber 15 via orifice 28 in a manner tobe described, a second plate 23 also having as uare or polygonal centralorifice formed t erethrough coacting with correspondingly shapedportions of shaft 17, plate 23 having a pair of openings 3G and 31positioned to move acrossair intake passages 32 and 33 when shaft 17 isrotated, a machined lateral surface 24 covering the face of plate 22 anda second machined surface 25 covering the face of plate 23, a. spring 26tending to apply plates 22 and 23 firmly against surfaces 24 and 25, anda plug 35 having an air inlet passage 34 positioned to communicate atopposite extremities with the air and with chamber 15.

The hereinabove described assembly oprates in the following manner:

Assuming the motor to be cold and at-rest and throttle valve 6 in closedosition, that is to say so as to completely block mixing chamber 5 andpartially cover the discharge orice oi auxiliary mixing chamber 4(Figure 1), and that it bey desired to start the motor While cold and tomaintain the latter in rotation until warm, lever 18 is displaced so asto rotate shaft 17 and bring plates 22 and 23 into the position shown inFigures 1 and 3. Main mixing chamber 5 is then in communication withchamber 15 via passage 16 and oriiiee 27, while, at the Sametime,chamber 15 communicates with main cham ber 5 downstreamward of throttlevalve 6 via passage 2C and orifice 28. At this stage, plate 23 cuts olfcommunication between chamber 15 and air inlet passages 32 and 33, whilepassage 34 continues to supply air from the atmosphere to said chamber.If the position. and dimensions of the various passages and oriiices aswell as the design of elements 12, 13 and 14 are chosen to give a propermixture during cold operation and slow speed, the motor will at oncestart when turned over, the supply of fuel from orifice 8, will bedependent on the duid pressure transmitted from the constant levelchamber and the carburetion will vary automatically in accordance withthe changes of speed of the motor resulting from the diminution of itsinternal resistance (varying viscosity of the oil, etc.). The form,dimensions and position of the various passages communicating withchamber 15 permit regulation of the transition in operation from theauxiliary'carburetor assembly to the main carburetor assembly. Inasmuchas chamber 15 communicates via passages 16 and 29 with opposite sides ofthe throttle valve, it'creates a depression in the malumixing chambertending to maintain prinelpal nozzle 3 ready to supply fuel as soon asthe throttle valve is opened. In order to insure a gradual transition,when ,shaft 17 is rotated to cut out the auxiliary carburetor assembly,air inlets 32 and 33 and orifices 30 and 31 are positioned so as toreplace the air formerly entering via passage 29 and orice 28. As soonas shaft 17 is turned so as to cut 0E communication at 28-29 and 16-27,the auxiliary carburetor no longer supplies fuel to mixing'hamber `5. Atthat time, passages 30, 32 and31-33 establish communication betweenchamber 15 and the atmosphere. If, because of leakage, art of thedepression in main mixing cham er 5, is transmitted to chamber l5, theopening of passages 30-32 and 31 prevents fuel being fed from conduit13.

Figure 3 shows, in full lines, the relative position of orifices 27 and28 relatively to passages 16 and 29 when shaft 17 is in open position(Figure 1). At that time passages 32 and 33, shown in dotted lines, areout of alignment with orifices 30 and 31.

Figure 4 shows the position of the various operating elements when shaft17 is turned into closed osition, oriiices27 and 28 (dotted lines) beingout of line with passages 16 and 29, while passages 32 and 33 (fulllines) are in alignment with orifices 30 and 31.

The form of carburetor represented in Figures 5 and 6 differs from theone already described only in that mixing chamber 5 lis horizontalrather than vertical. This carhuretor assembly functions substantiallyin the same manner as the one illustrated in Figures 1 to 4.

In practice, it is found that the mixture entering the main mixing`chamber through passage 16 arrives under considerable velocity and that,unless the discharge end of passage 16 be positioned along a plane ofsymmetry bisecting elements 36, 37 and 38, the mixture is not evenlydistributed among the cylinders.

In the claims that follow the term a conduit system is meant to includeelements 16. 15 and 29. Y

What I claim is :-T

1. In combination with a carburetor provided with a main nozzle, a mainmixing chamber and a throttle valve controlling said mixing chamber. anauxiliary carburetor assembly comprising a chamber. passagescommunicating at opposite extremities with said chamber and with saidmain mixing chamber at points positioned on opposite sides of saidthrottle valvewhen the latter is in closed position, said chambercommunicating with the atmosphere, means operative by the depression insaid main mixing chamber to aspirate fuel into said chamber of saidauxiliary carburetor assembly, and a valve assembly operative to controlcommunication between said passages and said chamber, said chamberhaving additional communication to the atmosphere comprising a passagepositioned to communicate at one extremity with the atmosphere and atits other extremity with said chamber via said valve assembly.

2. In combination with a main carburetor assembly including a mainnozzle. a main mixing chamber, an auxiliary nozzle, an auxiliary mixingchamber communicating with said main mixing chamber, and a throttlevalve simultaneously controlling said mainpassagesvv communicating atopposite extremities with said chamber and with said mainV mixingchamber at-point-s situated on opposite sides of said throttle valvewhen the latter is in closed position, said chamber communicating-withthe atmosphere, means opconstant level chamber, a main mixing chamberositioned to receive fuel discharged from sai main nozzle, and athrottle valve positioned inside said main mixing chamber, a

conduit system having a pair of terminal oriiices positioned tocommunicate with said main mixing chamber at points situated on oppositesides of said throttle valve when the latter is in closed position, apassage communicating at opposite extremlties with the atmosphere andwith said' conduit system, a well communicating with the atmosphere andsupplied with fuel from said constant level chamber, a tubecommunicating at opposite extremities with said conduit system and with'the fuel contained' in said well, a second passage positioned tocommunicate at opposite extremities with the atmosphere an with saidconduit system. and a valve operative 40 to simultaneously controlcommunication between said second passage and said conduit system, andbetween said main mixing chamber and portions of said conduit system.

4. In combination with a. main carburetor assembly including a constantlevel chamber, a main nozzle provided with fuel from said constant lev lchamber, a vmain mixing chamber positioned to receive fuel dischargedfrom said main nozzle, and 'a throttle valve positioned inside saidmaixr'mixing chamber,

a conduit system having a pai1`7,\of terminal orifices positioned tocommunicate with said main mixing chamber at points Asituated onopposite sides of `said throttle valve when the latter is in'- closedposition, a passage communicating at opposite extremities'with theatmosphere and with said conduit system, a-

well communicating withthe atmosphere and vsupplied with fuel .from saidconstant level chamber, a tube communicating at opposite extremitieswith said conduit system and with thefuel contained in saidfwell, asective to simultaneously cut o communication between said last namedpassage and said conduit system and to establish communication betweensaid main mixing chamber and portions of said conduit system, said valvebeing also operative to establishv communi-V cation between said lastnamed passage and said conduit system while cutting oif com- .municationbetween said main mixing chamber and portions of said conduit system.

5. In combination with a main carburetor assembly including a constantlevel chamber,

a main nozzle communicating with saidconstant level chamber, a mainmixing chamber positioned to receive fuel discharged from said nozzle,and a throttle valve positioned -inside said main mixing chamber,-anauxiliary carburetor assembly comprising a well communicating at'opposite extremities with the atmosphere and with said constant levelchamber, a tube extending into said well and having a free yextremitypositioned to lie -below the level of fuel contained in the latter, achamber communicating with said tube,a first passage extending from saidchamber to a point in the wall of said main mixing chamber situatedupstreamwar'd with relation to said throttle valve, a second passageextending from said chamber to a point in the wall of said main mixingchamber situated downstreamward with relation to said throttle valvewhenl the latter is in closed position, a third passage communicating atopposite extremities with the atmosphere and with said chamber, a discmounted inside said chamber and having oriices formed therethroughpositioned to move across said first and second passages at the pointswhere the -latter communicate with said chamber, and means for'rotatingsaid disc.

6. A structure as defined in claim 5 in combination with an auxiliarynozzle, and an auxiliary mixing chamber communicating with said nozzleand with said main mixing Y chamber.

7 A structure as defined in claim 5in combination with a second discmounted inside said chamber and having an orifice formed thereinpositioned to move across said third passage, said second disc beingrotatable by said last named means.

8. A structure as defined in claim 5 in combination with a `second discmounted insidev said chamber and having an orificeA formed thereinpositioned to move across said third passage, said second disc beingrotatable by said last named means, and a spring tending to move saiddiscs apart.

In testimony whereof I aix my signature.

M. MENNESSON.

ond passage positioned to communicate at opposite extremities with theatmosphere and with said conduit system, and a valve opera-

